{3.3} Suppose that A M5 7(R) and dim null(A) = 2. What is the rank of A7 Are the columns of A linearly dependent? Do the non-leading columns of A form a basis for the null space of A7 Is there necessarily a row of zeros is the reduced row-echelon form of A7 Is there necessarily a column of zeros in the reduced row-echelon form of A? For which values of A is null(A) a subspace of RF? Can the linear system Ax = b be inconsistent for some choice of b? Will the linear system Ax = 0 have a unique solution